This invention relates to an apparatus for a chorus effect in an electronic musical instrument.
There is already known in the art an arrangement where, as shown in FIG. 1, a passing circuit 1 for a musical tone signal is provided with a tone color filter 2 interposed therein and an output terminal of the filter is diverged to plural delay circuits 3-1 . . . 3-3, and the output terminals thereof are connected to speakers 6-1 . . . 6-3 through low-pass filters 4-1 . . . 4-3 and amplifiers 5-1 . . . 5-3, respectively. The delay circuits 3-1 . . . 3-3 are arranged to be controlled by switching oscillators 7-1 . . . 7-3. Numeral 8 denotes a low frequency oscillator, and an output terminal thereof is connected to the switching oscillators 7-1 . . . 7-3 through a phase-shift circuit 9. An ensemble effect can be obtained as a result of the fact that the delay circuits 3-1 . . . 3-3 are given periodically delay changes by such respective pulses generated from the switching oscillators 3-1 . . . 3-3 that are changed in cycle and different in phase from one another. (See: Japanese Patent Publication Sho 52-38888).
This arrangement is comparatively excellent in ensemble effects such as for strings, brasses or similar instruments but it is difficult to obtain a chorus effect of a human voice.
It is, therefore, an object of the present invention to provide an apparatus for obtaining a chorus effect very similar to the human voice.
Another object of the present invention is to provide apparatus of the foregoing character which is substantially simple in construction and may be economically fabricated.
A further object of the present invention is to provide an arrangement, as described, which may be readily maintained in service and which has a substantially long operating life.